Re: [PATCH 13/17] staging: lustre: lloop: Fix build failure on ppc64

[James Simmons <jsimmons@infradead.org>]

> This patch was shown not to work. I just haven't removed it from opensuse yet.

Its been running in our production tree as well for some time. Guess that 
change is a noop. In any case we have been discussing redoing the lloop 
driver anyways. Just need to find the cycles.

> --
> Jeff Mahoney
> (apologies for the top post -- from my mobile)
> 
> > On Apr 10, 2016, at 9:13 AM, James Simmons <jsimmons@infradead.org> wrote:
> > 
> > From: Jeff Mahoney <jeffm@suse.com>
> > 
> > On ppc64 with 64k pages, we get a build failure in lloop:
> > 
> > drivers/staging/lustre/lustre/llite/lloop.c:527:2:
> > note: in expansion of macro 'CLASSERT'
> > CLASSERT(PAGE_CACHE_SIZE < (1 << (sizeof(unsigned short) * 8)));
> > 
> > There's no need to change the queue's logical block size. Even if it could
> > accept a 64k value, that would result in any file system on top of it
> > needing to also use 64k blocks. It'd be safe to set it to 4k, but there's
> > no actual need for it. It's not used to split requests except for WRITE_SAME,
> > which lloop doesn't implement anyway.
> > 
> > Signed-off-by: Jeff Mahoney <jeffm@suse.com>
> > Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4000
> > Reviewed-on: http://review.whamcloud.com/7745
> > Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
> > Reviewed-by: Minh Diep <minh.diep@intel.com>
> > Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
> > Signed-off-by: James Simmons <jsimmons@infradead.org>
> > ---
> > drivers/staging/lustre/lustre/llite/lloop.c |    3 ---
> > 1 files changed, 0 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/staging/lustre/lustre/llite/lloop.c b/drivers/staging/lustre/lustre/llite/lloop.c
> > index b725fc1..f396753 100644
> > --- a/drivers/staging/lustre/lustre/llite/lloop.c
> > +++ b/drivers/staging/lustre/lustre/llite/lloop.c
> > @@ -525,9 +525,6 @@ static int loop_set_fd(struct lloop_device *lo, struct file *unused,
> >    lo->lo_queue->queuedata = lo;
> > 
> >    /* queue parameters */
> > -    CLASSERT(PAGE_CACHE_SIZE < (1 << (sizeof(unsigned short) * 8)));
> > -    blk_queue_logical_block_size(lo->lo_queue,
> > -                     (unsigned short)PAGE_CACHE_SIZE);
> >    blk_queue_max_hw_sectors(lo->lo_queue,
> >                 LLOOP_MAX_SEGMENTS << (PAGE_CACHE_SHIFT - 9));
> >    blk_queue_max_segments(lo->lo_queue, LLOOP_MAX_SEGMENTS);
> > -- 
> > 1.7.1
> > 
> > 
> 
>